Basic oxygen steelmaking vessels



Jan. 3, 1967 A, E. HNN 3,295,845

BASIC OXYGEN STEELMAKING' VESSELS Filed Sept. 20, 1965 v 2 Sheets-Sheet 1 Fig.1

//Vl /V70/ ALFRED E. FINN Jan. 3, 1967 FlNN 3,295,845

BASIC OXYGEN STEELMAKING VESSELS Filed Sept. 20, 1965 2 Sheets-Sheet 2 INVENTOR.

ALFRED E. F'INN United States Patent M 3,295,845 BASIC OXYGEN STEELMAKING VESSELS Alfred E. Finn, Pittsburgh, Pa., assignor to Harbison- Walker Refractories Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed Sept. 20, 1965, Ser. No. 488,386 5 Claims. (Cl. 266 -36) The present invention relates to basic oxygen steelmaking vessels and more particularly, to prefabricated, highly refractory tapholes for such vessels.

It has been standard practice in the steel industry to form basic oxygen furnace tapholes from dead burned magnesite refractories having a high MgO content, since magnesite is one of the best basic refractories known for contact with molten metal in basic steelmaking furnaces, and for resisting the high temperatures and chemical attack which occur in the operation of such furnaces.

Heretofore, basic oxygen furnace tapholes have been formed in a variety of ways; One such mode of installation was by ramming successive layers of magnesite grain about a steel pipe passing through the taphole opening in the furnace shell and opening into the furnace chamber until the taphole area was completely filled with the refractory. However, owing to the structure and location of the tapholes, it was found diflicult to ram all of the interstices or crevices in the taphole area and to obtain high densities thereby. The same difficulties were encountered in completely vibration casting the taphole area. There will be noted subsequently from the drawings that the taphole area, if located in the cone section of the furnace, as in the basic oxygen furnace, is not an ideal place to endeavor a vibration cast taphole. Another objection to the above method is that vibration casting mixes typically contain between'7 and 8% of Water, and the water must be removed during burnin. This requires higher temperatures and a relatively long burn-in schedule which extends the down-time of the vessel. It is important that the refractory employed for the taphole and the technique used to install it be compatible with the burn-in schedule of the refractory lining of the basic oxygen furnace since it comprises the bulk of the furnace.

Accordingly, there has been a long existing need in the art for reducing the time required to install a basic oxygen furnace taphole; for eliminating the lack of uniformity inherent in rammed and vibration cast tapholes; and for significantly reducing the maintenance and repair costs and furnace down-time involved for delays in taphole area repairs in the operation of the basic oxygen furnaces.

Therefore, it is an object of the present invention to provide a novel, integral, uniform, dense, highly refractory taphole in a basic oxygen furnace which substantially reduces the time heretofore required for installing or replacing basic oxygen furnace tapholes.

Another object of the invention is to provide a prefabricated, highly refractory taphole in a basic oxygen furnace which is compatible with the bumin schedule of the refractory lining in the remainder of the furnace.

Other objects of the invention will be apparent hereinafter.

In the drawings:

FIG. 1 is a perspective view, partly broken away, of a basic oxygen furnace, particularly showing the taphole side of the furnace;

FIG. 2 is a perspective view of a prefabricated taphole for use in basic oxygen furnaces, according to the present invention; and,

FIG. 3 is an elevation view of shapes used in fabricating tapholes.

In accordance with the present invention, there is provided a prefabricated taphole assembly in the cone section 3,295,845 Patented Jan. 3, 1967 zone of basic oxygen converter vessels of the type having a generally circular barrel zone and a downwardly opening truncated cone section zone. The assembly is composed of a plurality of mated pairs of refractory brick shapes. The individual brick and each pair have generally face, side, and end surfaces. Each brick contains a groove in a face surface thereof which intersects at least two of the other surfaces. Each pair of brick defines a portion of an inclined taphole. The pairs are arranged one over'the other to provide a continuous inclined taphole extending through the brick assembly.

Referring to FIG. 1, there is shown a basic oxygen furnace 10 consisting of an outer metal shell 12, a shell protective brick lining 14in contact with'the inside surface of the shell and a brick working lining 16. The vessel is constructed of three major'zones, the bottom zone 18, the barrel zone 20, and the cone section 22. 'The bottom zone is dish shaped and of upwardly opening concave configuration. The brick 23 in the bottom zone terminate at the'barrel zone 20' with their face surfaces inclined from the bottom upwardly to the cone section zone. The working lining brick 14 in both the barrel and the cone section zones are disposed so that their face surfaces are in the horizontal plane. The cone section zone, having a taphole area 26, extends upwardly and terminates in theform of a mouth 28 at the top of the vessel. The cone section zone is of downwardly opening truncated cross-sectional configuration.

Disposed in the taphole area of the vessel is a taphole assembly 30 according to the present invention (best shown in FIG. 2). The taphole assembly 30 is composed of two mated pairs 32 and 34 of refractory brickshapes. The individual brick in each pair contain generally face, side and end surfaces.

Referring to FIG. 3, there is shown the righthand sided brick 32b and 34b-of the taphole assembly shown in FIG. 2. The brick 32b contains a groove 36 in the face surface 38 thereof. The groove intersects the end surface 40 and the side surface 42. The brick'34b contains a groove 44 that intersects the end surface 46 and the side surface 48. The angle of the groove formed through both brick is dependent on the inclination of the taphole opening. Thus, if the angle of the groove with respect to the horizontal were of greater value than that shown, the grooves could intersect three surfaces of each of the brick 32b and 34b. The end surfaces 42, 43, 45 and 46, are unidirectionally inclined to the side surfaces of the respective brick 32b and 34b to conform in contour to the truncated cone section zone. Each of the brick could be of a true parallelogram cross-sectional configuration depending upon the bias of the cone section zone.

The other brick 32a and 34a of each mated pair 32 and 34 are of similar configuration. Actually, when placed together as shown in FIG. 2 the pairs of brick are mirror images of each other, so that each pair of brick define a portion of the inclined taphole. The pairs 32 and 34 are arranged one over the other to provide a continuous inclined taphole extending through the taphole assembly.

While FIG. 2 shows that there are two pair of refractory brick stacked one on top of the other, other pairs could conceivably be stacked on top of the pairs shown, if the inclination of the taphole is somewhat greater than that shown in FIG. 1.

In practice, the taphole assembly of the present invention can be placed in the basic oxygen vessel shown in FIG. 1, readily and with a minimum of labor. Each of the mating faces of the refractory brick 32a, 32b, 34a, and 34b may be clipped in a mortar slurry, if desired, before assembly thereof. After the brick in the barrel zone are stacked up to the cone section zone and the taphole opening, the taphole assembly is merely laid and mortared a minimum amount of rammed fill so that the continuous inclined taphole is in alignment with the taphole opening 50 through the furnace shell. Then the cone section zone, in the taphole area, is 'laid'in the normal manner.

As shown in FIG. 1, the inclined end surfaces of the brick are contiguous with the shell protective lining. The remainder of the taphole opening may 'be readily fabricated by inserting a pipe in alignment with the prefabricated inclined taphole and then filling around the pipe with a monolithic refractory material from exterior the furnace.

Further, the taphole opening in the mated pairs 32 may be provided with a female socket which extends from the cold face thereof. The extending socket is secured to one end of the pipe to insure continuous alignment and connection therewith.

The individual brick of the taphole assembly could be composed of highly refractory, dead burned magnesite processed to high densities as are the remainder of the brick lining the vessel; so that the bumin schedule of the taphole would be similar to the burnin schedule of the remainder of the lining and the problems heretofore encountered with differently fabricated tapholes would not occur. However, it is not intended that the taphole construction of present invention be limited to magnesite shapes. Other basic refractories conventionally used in the basic oxygen furnace are suitable.

While the invention has been described with reference 8 to basic oxygen steelmaking vessels, it should not be limited thereto, as the prefabricated taphole assembly of the type shown could be utilized with other vessels requiring an inclined taphole.

Having thus described the invention in detail and with sufficient particularity as to enable those skilled in the art to practice it, what is desired to have protected by Letters Patent is set forth in the following claims.

I claim:

1. In metallurgical vessels of the type having an outer metal shell, a refractory lining in contact with the interior of the shell and an inclined taphole opening passing through the metal shell, the improvement comprising a prefabricated taphole assembly opening into said taphole opening composed of a plurality of mated pairs of refractory brick having generally face, side and end surfaces, each brick in each of said pairs containing a groove in a face surface thereof, said groove extending entirely across the face surface in which it is formed and intersecting an adjacent side and end surface which side and end surface intersect to form a common edge, both brick in each pair being arranged so that the respective groove containing face surfaces are in contiguous contact with each other with said respective groove containing faces cooperating to define an open ended passage which forms a portion of an inclined taphole, a said pair of brick being arranged with its side surfaces in contiguous contact with an adjacent pair along a vertical axis of the vessel with respective open ended passages aligned to provide an open ended continuous inclined taphole, with respect to said vertical axis, extending through the brick assembly.

2. The vessel of claim 1 in which the taphole assembly consists of two pairs of refractory brick shapes.

3. The vessel of claim 1 in which the end surfaces of the individual brick in the taphole assembly are unidirectionally inclined to the side surfaces thereof.

4. The vessels of claim 1 in which each of the brick shapes is a parallelogram in cross-section but having sloped ends and in which each brick shape of each mated pair is a mirror image of the other.

5. The vessel of claim 1 in which the metallurgical vessel is a basic oxygen converter of the type having a generally circular open topped barrel zone and a downwardly opening truncated cone section zone superposed there over and said taphole assembly opens into the cone section zone.

References Cited by the Examiner UNITED STATES PATENTS 393,136 11/1888 Young 182.5

806,621 5/1905 Baggaley 26636 2,125,193 7/1938 Morlock 26643 3,084,924 4/1963 Morlock 26641 3,148,238 9/ 1964 Willenbrock 266-43 3,153,110 10/1964 Sherburn et al 266-38 3,227,434 1/1966 Voet et a1 26636 JOHN F. CAMPBELL, Primary Examiner.

J. M. ROMANCHIK, Assistant Examiner. 

1. IN METALLURIGAL VESSELS OF THE TYPE HAVING AN OUTER METAL SHELL, A REFRACTORY LINING IN CONTACT WITH THE INTERIOR OF THE SHELL AND AN INCLINED TAPHOLE OPENING PASSING THROUGH THE METAL SHELL, THE IMPROVEMENT COMPRISING A PREFABRICATED TAPHOLE ASSEMBLY OPENING INTO SAID TAPHOLE OPENING COMPOSED OF A PLURALITY OF MATED PAIRS OF REFRACTORY BRICK HAVING GENERALLY FACE, SIDE AND END SURFACES, EACH BRICK IN EACH OF SAID PAIRS CONTAINING A GROOVE IN A FACE SURFACE THEREOF, SAID GROOVE EXTENDING ENTIRELY ACROSS THE FACE SURFACE IN WHICH IT IS FORMED AND INTERSECTING AN ADJACENT SIDE AND END SURFACE WHICH SIDE AND END SURFACE INTERSECT TO FORM A COMMON EDGE, BOTH BRICK IN EACH PAIR BEING ARRANGED SO THAT THE RESPECTIVE GROOVE CONTAINING FACE SURFACES ARE IN CONTIGUOUS CONTACT WITH EACH OTHER WITH SAID RESPECTIVE GROOVE CONTAINING FACES COOPERATING TO DEFINE AN OPEN ENDED PASSAGE WHICH FORMS A PORTION OF AN INCLINED TAPHOLE, A SAID PAIR OF BRICK BEING ARRANGED WITH ITS SIDE SURFACES IN CONTIGUOUS CONTACT WITH AN ADJACENT PAIR ALONG A VERTICAL AXIS OF THE VESSEL WITH RESPECTIVE OPEN ENDED PASSAGES ALIGNED TO PROVIDE AN OPEN ENDED CONTINUOUS INCLINED TAPHOLE, WITH RESPECT TO SAID VERTICAL AXIS, EXTENDING THROUGH THE BRICK ASSEMBLY. 